The present invention relates to double-ended tuning fork (DETF) vibrating beam force transducers. More particularly, the invention relates to an improvement that reduces the DETF's handling fragility and mounting stresses.
The design and application of DETFs is a maturing art in the field of pressure transducers, accelerometers, scales and other instrumentation applications where the physical effect being measured can be converted to a force and the force, in turn, applied to the DETF vibrating beam force transducer. The force then modulates the frequency of the vibrating beam. The use of frequency modulated vibratory sensors has always been attractive in instrumentation applications due to the inherent digital nature of the output signal without the need for A/D conversion. When the sensor material used is quartz crystal, excellent stability of bias frequency and span is realized as well as low temperature sensitivity. In addition, the piezoelectric property of quartz crystal provides a simple means of sustaining beam vibrations using an oscillator circuit electrically connected to electrodes plated on the crystal resonator.